Air and Atmosphere is one of the important chapters which students can learn in ICSE Model Paper Class 7 Chemistry provided by the Extramarks app. By learning ICSE Model Paper Class 7 Chemistry students will know that air, a combination of gases that compose the atmosphere of the Earth. The mixture contains a group of nearly constant concentrations of gases and a group of variable space and time concentrations. Mixing associated with atmospheric motions preserves the uniformity of composition; however, above a height of about 90 km (55 miles), diffusional processes become more important than mixing, and the lighter gases are more abundant above that point. Of the variable concentrations among gases, water vapor, ozone, carbon dioxide, sulfur dioxide, and nitrogen dioxide are of primary importance. Though present in relatively small amounts, these variable constituents may be very important to sustain life on the surface of Earth. Water vapor is the source of all types of precipitation and is an effective absorber and emitter of radiation from the infrared. Carbon dioxide is also an effective absorber and emitter of infrared radiation, in addition to being involved in the photosynthesis process. Ozone, which is present mainly in the atmospheric region 10 to 50 km above the surface of the Earth, is an effective absorber of Sun ultraviolet radiation and effectively shields the Earth from all wavelength radiation of fewer than 3,000 angstroms. For the full chapter summary of the Air and Atmosphere, students can take online classes for ICSE Chemistry Sample Paper for Class 7 from the Extramarks app. 'Language of Chemistry' is the scoring chapter which is covered in ICSE Chemistry Sample Paper for Class 7. The matter is anything that takes up space, has mass, and offers resistance. A matter is divided up basically into physical and chemical groups. Chemistry is a research division concerned with material properties, transformation, and composition. A matter is something that takes up space, has mass, and provides resistance. The sum of matter that a body contains is known as its mass. The force which the gravitational force exerts on an object is called its weight. The matter is physically classified into three states: solid, liquid, and gas. Chemically, the matter is divided into substances that are pure and impure (mixture). For full notes on the Language of Chemistry, students can take online classes for ICSE Chemistry Sample Paper for Class 7 from the Extramarks app. Students who want ICSE Class 7 Chemistry Question Paper for practice then they can download it with the help of the Extramarks app.
